1. Field of the Invention
The present invention relates to a covered endoscope having a dilation tube coupled to a dilation tube cap, where the cap is shielded with a cap cover.
2. Description of the Related Art
Endoscopes have been widely adopted in the field of medicine in recent years. When an endoscope for a medical use is inserted into a living body, body fluid or the like sometimes adheres to an observation window formed at the distal end of an insertional part, and disables clear observation. To overcome this drawback, an air supply channel or a water supply channel is incorporated so that the body fluid or the like adhering to the observation window can be removed by spraying fluid on the observation window using a hand-held operational device. Some endoscopes are provided with a suction channel for sucking unnecessary body fluid or the like and discharging it.
Some endoscopes have a forceps (treatment adaptor) channel in order to enable collection of tissues using biopsy forceps or treatment using treatment adaptors.
In an endoscope having a channel such as the foregoing air supply channel or forceps channel, after the endoscope is applied to a patient, cleaning or disinfection is carried out in order to prevent infection. It takes, however, excessive time to achieve perfect cleaning or disinfection, which deteriorates the use efficiency of an endoscope. Another problem is that disinfection work is cumbersome.
An endoscope cover-sheathed endoscope has been proposed accordingly, wherein an endoscope itself is sheathed with an endoscope cover and then put to use. A used endoscope is kept out of dirt and need not be cleaned or disinfected.
For example, U.S. Pat. No. 4,991,565 has disclosed a cover for sheathing an insertional part of an endoscope, wherein an insertional endoscope part is inserted into the cover (or sheath). In an effort to simplify insertion or removal of the insertional endoscope part into or from the cover, air is fed from a dilator to the cover into which the insertional endoscope part is inserted, thus dilating the cover.
The cover is, therefore, provided with a dilation tube cap for guiding the air drawn with the dilator to the portion into which the insertional endoscope part is inserted. A dilation tube is coupled with the dilation tube cap, and the cover is dilated with the air supplied from the cover dilator. This permits easy sheathing.
A flange is formed on the dilation tube cap so that when the distal end of the dilation tube is coupled with the dilation tube cap in such a manner that the distal end shields the tube cap, the dilation tube will not come off.
When an endoscope is unsheathed from the cover, however, the cover becomes contaminated with body fluid or the like in a body cavity. The dilation tube cap formed on the cover also becomes contaminated. The dilation tube also gets contaminated when coupled with the dilation tube cap.
When the endoscope is sheathed with a new cover using the dilation tube, the portion of the dilation tube coupled with and brought into contact with the dilation tube cap gets contaminated. When a glove touches the contaminated dilation tube cap, the entire cover gets contaminated via the glove.